This invention relates generally to the art of hazardous-waste disposal and more specifically to a system for protecting people from fumes given off by discarded chemical liquids.
Many laboratories, both industrial and academic, discard large amounts of hazardous chemical liquids on a continuous basis. Such hazardous liquids are often continuously drained into hazardous-liquid containers through tubes, and when the hazardous-liquid containers are filled they are emptied. Because such collection containers must be vented to allow proper drainage, they often give off noxious gases, which are released into the atmosphere thereby polluting air breathed by personnel working around the hazardous-liquid collection containers. In addition to being offensive, these fumes can also be flammable, and therefore quite dangerous.
Thus, it is an object of this invention to appropriately clean fumes and gases escaping from discarded liquids in hazardous-liquid collection containers.
Another dangerous problem related to such hazardous-liquid collection containers is that when they are capsized the hazardous liquids therein escape through exhausts and other openings. Thus, it is another object of this invention to provide an exhaust-opening assembly for a hazardous-liquid collection container that not only reliably cleans noxious fumes escaping from the containers but which also prevents the hazardous liquids themselves from spilling from the containers if they are capsized.
It is still another object of this invention to provide a filter assembly for a hazardous-liquid collection container that informs users when carbon of a filter thereof is exhausted.
Further, it is an object of this invention to provide a filter-valve assembly for hazardous-liquid collection containers that does not allow passage of noxious fumes when a filter-cartridge assembly thereof is removed.
According to principles of this invention, an exhaust-opening assembly for exhausting fumes from a hazardous-liquid collection container includes a filter-valve assembly that includes a valve poppet that is moveable to an open position in response to a filter-cartridge assembly being attached to a mounting-valve-unit housing by a filter-cartridge attaching mechanism and that is allowed to be moved by a resilient biasing device to a closed position in response to the filter-cartridge assembly being detached from the mounting-valve-unit housing.
In one embodiment, the valve poppet has fingers extending along an exit passage, which engage a neck portion of the filter-cartridge assembly when the filter-cartridge assembly is screwed into the exit passage to move the valve poppet away from a valve seat. When the filter-cartridge assembly is removed, the resilient biasing device presses the valve poppet against the valve seat for closing the exit passage.
The mounting-valve-unit housing extends about a substantial outer portion of the filter-cartridge assembly for protecting the filter-cartridge assembly upon the hazardous-liquid collection container capsizing.
The filter-cartridge assembly includes an orientation-responsive shut-off valve to prevent flow of hazardous liquids through filter-cartridge housings upon capsizing and litmus-like material, which can be seen from outside the housings, to inform users when carbon of a carbon filter element is exhausted.
In a preferred embodiment, the filter-cartridge assembly is divided into a first-stage coalescing filter and a second-stage carbon filter, with the orientation-responsive valve being in a coalescing-filter housing and the litmus-like material being at an exit end of a carbon-filter housing.